I've diagnosed two problems with the cruise control on my 88GT 5-speed. One is a control module that won't set cruise with the "tap up/tap down" button, and the other is a non-functioning clutch cruise control safety switch. Rock Auto has the control module, but nobody seems to have the clutch switch. Anyone have a source for a new switch?

Not sure where to send you for the safety switch. Some of the guys here have said that it is possible to open your original switch and clean the contacts then reinstall, you might want to give it a try prior to buying a new one.

If you are refering to the cruise release switch it is the same as the brake cruise release switch, PN 10024217. I found 2 diferent GM parts sellers listing it by that number.